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In vitro biochemical investigation of the antioxidant, anti-inflammatory and antithrombotic bioactivities of extracts fro Pangeo mountain originated organic grape products and their by-products with helth promoting properties (Bachelor thesis)

Μιχαηλίδης, Στέφανος/ MICHAILIDIS, STEFANOS

In the present study, the biochemical composition and biological activity of extracts derived from two grape varieties (Mavroudi and Sauvignon Blanc), the former’s wine, and its corresponding winemaking by-products were investigated. Both a green and a conventional extraction technique were employed for the recovery of total amphiphilic (TAC) and lipophilic (TLC) fractions. The extracts were evaluated in terms of their total phenolic and carotenoid content, antioxidant capacity (DPPH, ABTS, and FRAP assays), photoprotective properties, as well as their anti-inflammatory and antithrombotic activities. The results demonstrated that both the extraction method and fraction polarity significantly influence extraction yield and the content of bioactive compounds. Green extraction provided higher overall recovery, whereas conventional extraction favored the recovery of phenolic constituents. Wine-derived extracts exhibited the highest phenolic content and the greatest antioxidant activity, while the winemaking by-products retained substantial amounts of bioactive compounds and, consequently, showed remarkable antioxidant capacity. Furthermore, the highest carotenoid concentrations were recorded in conventionally extracted red grapes and their corresponding by-products. Spectroscopic analyses confirmed the presence of phenolic compounds, carotenoids, and functional groups associated with lipid constituents, whereas UV-Vis data revealed strong absorption in both the UVA and UVB regions, indicating significant photoprotective potential. In parallel, all extracts, particularly those derived from the winemaking by-products, inhibited platelet aggregation through both PAF- and ADP-induced pathways, suggesting anti-inflammatory and antithrombotic properties, most likely due to the presence of phenolic bioactive compounds and polar lipids rich in unsaturated fatty acids, consistent with the structural characterization provided by ATR-FTIR analysis. In addition to these findings, limitations related to extraction optimization, assay sensitivity, and the exclusively in vitro nature of the study are also discussed. Overall, the results support the view that Mavroudi winemaking products and by-products constitute promising and sustainable sources of functional compounds with potential applications in the food, health, and cosmetic industries